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The city transit system |
2001-01-07 |
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From Jacky:
The city transit system carries an average of 9450 bus riders a day, for a fare of $1.75 each. The city wants to reduce car pollution by increasing ridership and to maximize the transit system's revenue at the same time. A survey indicates that the number of riders will increase by 150 for every $0.05 decrease in fare.
Answered by Harley Weston. |
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Women mathematicians |
2001-01-07 |
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From Kisha:
Can you please tell me names of at least five female math teachers who changed history back then?
Answered by Penny Nom. |
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Derfs, Enajs and Sivads |
2001-01-07 |
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From John and Norman:
All Derfs are Enajs. One-third of all Enajs are Derfs. Half of all Sivads are Enajs. One Sivad is a Derf. Eight Sivads are Enajs. The number of Enajs is 90. How many Enajs are neither Derf nor Sivad?
Answered by Penny Nom. |
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A dollar, quarter, dime, nickle and penny |
2001-01-07 |
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From Sarah:
Arnold has a dollar coin, one dime, one quarter, one nickel, and a penny. The number of different sums of money that can be formed using three coins is...
Answered by Penny Nom. |
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The pythagorean theorem in everyday life |
2001-01-06 |
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From Josh:
What are some ways that we use the pythagorean theorem in jobs, or even in everyday life?
Answered by Claude tardif. |
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Two questions |
2001-01-04 |
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From Justine:
first: A diagonal of a rectangle is the square root of 13 meters and the area of the rectangle is 6 meters squared. What are the dimensions of the rectangle? last: Find the ordered triple of nonzero digits (A,B,C) for which (AA)squared=BBCC where AA and BBCC are respectively, two-digit and four-digit base-ten numerals.
Answered by Penny Nom. |
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Radical de n |
2001-01-03 |
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From Un eleve:
j'aimerai savoir ( d.Levy), élève de 1éS ce que signifie la phrase: radical de 2 + radical de 3 est un nombre négatif ( niveau intérmédiaire).
Answered by Claude Tardif. |
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Three dice |
2001-01-03 |
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From John Read:
I have three dice (A, B, C.) Three sides of each dice are blank. Three sides of each dice have a number. When the dice are thrown, it must be possible to result in the numbers 1 to 49 in any combinations without doubling up on any figure. i.e. Different combinations resulting in the same end number. I managed to get from 1 to 47 before getting stuck.
Answered by Claude Tardif. |
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Why the change from commas between every 3rd digit, to spaces instead? |
2001-01-03 |
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From Clarende Duby:
Why the change from commas between every 3rd digit, to spaces instead? For example: Three million three hundred thirty-three thousand three hundred thirty-three written like: 3 333 333 instead of 3,333,333? Does it have something to do with standardizing mathematical notation worldwide?
Answered by Harley Weston. |
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30% of 80 |
2001-01-03 |
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From Denise:
Could you please tell me what 30% of 80 is?
Answered by Penny Nom. |
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The laws of sines and cosines |
2001-01-02 |
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From Faydene:
Can the sine /cosine rule be applied to a right -angle triangle to find a particular solution or are these 'rules' applied only when the triangle is not right angled?
Answered by Penny Nom. |
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Filling a tank |
2001-01-02 |
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From Liting:
Water flows into a rectangle tank which measures 4 m by 3 m by 2.8 m through a cylindrical pipe of radius 2.4 cm. If the rate at which the water flows into the tank is 8 km/h, find how long it takes to fill the tank.
Answered by Penny Nom. |
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Polite numbers |
2001-01-02 |
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From A student:
A positive whole number, greater than 1, is said to be a polite number if it can be expressed as a sum of consecutive whole numbers Find all the polite numbers less than 21. Find a pattern in the numbers that are not polite. Explain why every odd number greater than one must be polite.
Answered by Penny Nom. |
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A quarter-circle and two semi-circles |
2000-12-31 |
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From Christopher:
Inside the quarter-circle are two semi-circles with the same radius, (r). Which has a greater area, G or L?
Answered by Penny Nom. |
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Height of the lamp |
2000-12-31 |
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From Joey:
The figure shows a lamp located three units to the right of the y-axis and a shadow created by the elliptical region x2 + 4y2 < 5. If the point (-5,0) is on the edge of the shadow, how far above the x-axis is the lamp located?
Answered by Harley Weston. |
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